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Updated: Jul 19, 2026

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Synthesis and Characterization of 1,2-Dithiolane Modified Self-Assembling Peptides
Published on: August 20, 2018
A short water-soluble self-assembling peptide forms amyloid-like fibrils
Sudipta Ray1, Apurba K Das, Michael G B Drew
1Department of Biological Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India.
Summary
The tripeptide Val-Ile-Ala self-assembles into amyloid-like fibrils, mimicking Alzheimer's disease peptides. In contrast, Ala-Val-Ile forms branched structures without amyloid characteristics.
Area of Science:
- Biochemistry
- Materials Science
- Neuroscience
Background:
- Alzheimer's disease is linked to amyloid-beta peptide aggregation.
- Understanding peptide self-assembly is crucial for disease research.
- Tripeptides can mimic or contrast amyloidogenic behavior.
Purpose of the Study:
- To investigate the self-assembly behavior of Val-Ile-Ala (VIA) and Ala-Val-Ile (AVI) tripeptides.
- To compare the fibril formation and amyloid-like properties of VIA and AVI.
- To explore sequence-dependent self-assembly in peptide systems.
Main Methods:
- Synthesis of Val-Ile-Ala (VIA) and Ala-Val-Ile (AVI) tripeptides.
- Crystallization and structural analysis of self-assembled peptides.
- Characterization of nanofibril morphology and amyloid-like properties.
Main Results:
- VIA self-assembles into straight, unbranched nanofibrils with intermolecular hydrogen-bonded beta-sheet structures.
- VIA fibrils exhibit amyloid-like behavior, similar to Alzheimer's Abeta(40-42).
- AVI self-assembles into branched nanofibrils lacking amyloid characteristics.
Conclusions:
- The sequence of a tripeptide critically dictates its self-assembly pathway and resulting fibril morphology.
- VIA serves as a model for amyloid-like fibril formation.
- AVI's distinct self-assembly highlights the specificity of sequence in peptide aggregation.
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